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I think that this problem doesn't have an exact answer. Some time ago, I talked about this with the astrophysicist Paolicchi (this is the asteroid named after him) who works on the field. The conclusion is that debris are produced at random and you can only impose some ("few") constraints globally, say on big branches of the asteroids belt or of planetary ...

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When I read about this question, I was thinking, well, "a" can't be zero because it should represent your deceleration from 900 miles/hour. The resulting F would be the force you experience when you decelerate. (The deceleration depends on how you hit the obstacle, how long did it take you to stop/slow, across what distance, and the degree of deformity of ...

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Firstly, impulse is the change of momentum. Force is the RATE of change of momentum. The equation you have given is for force, not impulse. So, Force=change in (mass x velocity) / time of impact However, impulse, force* time= change in momentum. For example, if a car suddenly crashes with a wall, the passenger will continue to move in a straight line ...

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Since you are dealing with an inelastic collision, energy is not conserved when the bullet hits the block. You should try to find a relation between the initial velocity of the bullet and the velocity of the combined system (bullet+block) after the collision from conservation of momentum.

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Another way to think about Newton's second law (and the way he originally defined it) is $F=\dfrac{d\rho}{dt}$, where $\rho=mv$ is momentum and $\dfrac{d\rho}{dt}$ is the rate of change of momentum. I think you meant to say that the obstacle will exert a force on you - and that is correct. If you could calculate your change in velocity, and the amount of ...

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You're confusing the acceleration of your car with the acceleration in a collision. You actually have to look at it "backwards" from what you've described above. That is, in the collision you don't do a $F = ma$ calculation where $a$ is the acceleration of your gas pedal. Instead in the collision you have a force $F$ resulting from the collision and you ...

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For each case think about the total kinetic energy and number of cars that are available to absorb all of it during impact and it should be apparent which case has more energy (damage) per car. (crushing, deformation, sounds are evidence of energy conversion, so a tough rigid wall doesn't absorb any) A more challenging problem to intuition is (A) two cars ...

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I think the other two answers may have overlooked the source of your confusion, which is quite simple. The $F$ in $F=ma$ is the force being exerted on the object of mass $m$ to give it the acceleration $a$, not the force that that object will exert when it hits something. In the case of your example, the force of gravity on the basketball is independent of ...

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